In some situations symptoms are infrequent and thus even a week of heart rhythm monitoring may not be long enough. In these cases an implantable loop recorder may be surgically placed under the skin on the chest. The device that is implanted is the size of a small cigarette lighter and is introduced through a small incision in the skin usually less than an inch long.
The device has a battery life of up to 3 years. It will record the heart rhythm continuously as loops, deleting the previous recording unless a button is pressed on a small remote control that signals the device to store that period of recorded heart rhythm. Once a few recordings are saved the information can be downloaded using radiofrequency without removing the device. After a diagnosis has been made or the device battery is exhausted then it can be removed of if preferred left under the skin. The implantation and removal of the device is undertaken with local anaesthetic and some sedation. It takes about 15 minutes to perform.